Abstract Nitrogen-doped porous ultrathin layered carbon (LC) was prepared via annealing alkaline lignin with melamine and urea. As the anode material of sodium-ion batteries, the as-prepared LC shows high reversible capacity, outstanding rate performance and excellent cycling performance. In particular, the ultrathin graphitic carbon with large surface area and pore volume provide abundant sodium storage active sites, delivering a higher initial capacity of 320.5 mAh g−1 in the voltage range of 0.01–3 V at a current density of 0.1 C (1C = 30 mA g−1). Besides, the structure defects resulted from the doping of N also benefits to its high capacity. Capacitive and diffusion contribution calculation and EIS analysis proved the improved the Na+-ion storage kinetics due to LC's unique porous ultrathin structure, resulting in outstanding rate performance. LC delivers a high capacity of 138.7 mAh g−1 at 5 C. Besides, LC's porous ultrathin structure also guarantees its stable cycling performance. Even at a high current density of 5 C, there's no obvious capacity decay after 4000 cycles. This work presents an alternative approach for the synthesis of high-rate carbonaceous anode materials for sodium-ion batteries from low cost and sustainable feedstock.

中文翻译：

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木质素衍生的氮掺杂多孔超薄层状碳作为钠离子电池的高倍率负极材料

摘要 通过碱性木质素与三聚氰胺和尿素的退火制备氮掺杂多孔超薄层状碳（LC）。作为钠离子电池的负极材料，所制备的液晶显示出高可逆容量、优异的倍率性能和优异的循环性能。特别是，具有大表面积和孔体积的超薄石墨碳提供了丰富的钠存储活性位点，在 0.01-3 V 的电压范围内在 0.1 C (1C) 的电流密度下提供了更高的初始容量 320.5 mAh g-1 = 30 mA g−1)。此外，N掺杂导致的结构缺陷也有利于其高容量。电容和扩散贡献计算和 EIS 分析证明，由于 LC 独特的多孔超薄结构，改善了 Na+-离子存储动力学，导致出色的速率性能。LC 在 5 C 下可提供 138.7 mAh g-1 的高容量。此外，LC 的多孔超薄结构也保证了其稳定的循环性能。即使在 5 C 的高电流密度下，4000 次循环后也没有明显的容量衰减。这项工作提出了一种从低成本和可持续的原料合成用于钠离子电池的高倍率碳质负极材料的替代方法。